diff --git a/Chapter09/performance_profiling1.rs b/Chapter09/performance_profiling1.rs
index e69de29..327f36d 100644
--- a/Chapter09/performance_profiling1.rs
+++ b/Chapter09/performance_profiling1.rs
@@ -0,0 +1,20 @@
+use std::{thread,time};
+
+fn initialization() {
+   let t = time::Duration::from_millis(15000);
+   thread::sleep(t);
+}
+
+fn work() {
+   let t = time::Duration::from_millis(15000);
+   loop {
+      thread::sleep(t);
+      println!("Work.");
+   }
+}
+
+fn main() {
+   initialization();
+   println!("Done initializing, start work.");
+   work();
+}
diff --git a/Chapter09/performance_profiling2.rs b/Chapter09/performance_profiling2.rs
index e69de29..f79c691 100644
--- a/Chapter09/performance_profiling2.rs
+++ b/Chapter09/performance_profiling2.rs
@@ -0,0 +1,2 @@
+fn main() {
+}
diff --git a/Chapter09/performance_profiling3.rs b/Chapter09/performance_profiling3.rs
index e69de29..f79c691 100644
--- a/Chapter09/performance_profiling3.rs
+++ b/Chapter09/performance_profiling3.rs
@@ -0,0 +1,2 @@
+fn main() {
+}